^ Guards can merged without negative effect, dude.
So? Merge is a core part of the soviet faction design. Everything but shock troops can be merged without negative effect. For a well micored player the maximum reinforcement cost of any unit that isn't shocks is always going to be 20.
If you invest heavily guards and keep them all reinforced with one con squad you played the soviet faction design well, good job, A+ work.
They still take up more pop cap than conscripts, which is what distinguishes having one rather than the other. MP income and space for other stuff.